CHAPTER 17 URINARY SYSTEM

Transcription

1 CHAPTER 17 URINARY SYSTEM Albuminuria Anuria Dialysis Diuresis Dysuria Glycosuria Hematuria Micturition Oliguria Polyuria Pyuria Urinalysis Urination Void Journal question: How does the urinary system regulates the chemical composition of body fluids? Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 1

2 Chapter 17 Learning Objectives Define at least 10 terms relating to the urinary system. Describe the two functions of the urinary system. Identify four structures of the urinary system. Identify the function of at least three structures of the kidney. Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 2

3 Chapter 17 Learning Objectives Identify at least five components normally found in urine. Describe the possible cause of at least five abnormal components of urine. Describe at least three methods used to assess disorders of the urinary system. Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 3

4 Functions of the Urinary System Primary functions of the urinary system Regulation of the chemical composition of body fluids Removal of body wastes by filtering blood Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 4

5 Urinary System Parts of the urinary system Two kidneys Ureters Bladder Urethra Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 5

6 Urinary System FIGURE 17-1 The urinary system. (From Patton KT, Thibodeau GA: Anatomy & physiology, ed 7, St. Louis, 2010, Mosby.) Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 6

7 Kidneys The kidney is about 4 inches long and 2 inches wide, and it weighs about 150 g. Each kidney contains about 1 to 2 million nephrons (tiny structures that filter the blood). The kidney has three layers: Cortex (outer layer) Medulla: deep red Renal pelvis: funnel shaped Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 7

8 The Nephron FIGURE 17-2 The nephron. Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 8

9 Nephron Function Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 9

10 The Kidney FIGURE 17-3 The kidney. Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 10

11 Ureters Additional Components of the Urinary System Small tubes composed of smooth muscle tissue move the urine from the kidney to the bladder with peristaltic motion. Bladder A smooth muscular sac expands as it fills with urine. Nerves in the muscular wall are stimulated and cause the urge to urinate when the bladder is full. Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 11

12 Urethra Additional Components of the Urinary System Moves urine from the bladder to be excreted from the body Urinary meatus Opening at the end of the urethra through which urine passes to the outside of the body Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 12

13 Urine Formation Every minute, blood plasma enters the nephrons of each kidney through the renal arteries. In the nephron, particles are filtered from the blood to be eliminated by the body. Water, glucose, vitamins, amino acids, and chloride salts are resorbed into the blood in the renal tubules. Ammonia, potassium, hydrogen ions, and some drugs are secreted into the urine. Blood leaves the kidneys in the renal veins. Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 13

14 Characteristics of Urine Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 14

15 Urinalysis Assessment Techniques Series of tests determining urine composition by assessing Color Urine color normally varies from yellow to amber or straw. Clarity ph Normal urine is clear. Slightly acidic ph helps to prevent growth of bacteria. Specific gravity Measurement of the density of a liquid Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 15

16 Urinalysis Assessment Techniques Series of tests determining urine composition by assessing Odor Urine should have no odor. Volume Normal output is 1 to 1.5 L in 24 hours. Anuria means no urine output. Oliguria (less than 0.5 L output daily) may be caused by dehydration. Polyuria means an output of more than 2 L. Diuresis means a temporary increase in the amount of urine output. Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 16

17 Assessment Techniques Radiologic examination Used to detect the presence of stones in the urinary system Intravenous pyelogram (IVP) detects urinary blockage Series of x-rays taken as contrast medium is passes through the system (kidneys, ureter, bladder [KUB]) Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 17

18 Assessment Techniques Cystoscopy Used to examine the bladder A cystoscope is inserted into the urethra, and the bladder is inflated with water or air. Urodynamic tests Determines the force of the flow of urine through the system Rate measured with uroflowmetry Bladder and sphincter muscle control can be assessed. Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 18

19 Disorders of the Urinary System Cystitis Inflammation of the bladder caused by many types of bacteria Edema Abnormal accumulation of fluid in the tissue s intercellular space Nephritis Inflammation of the kidneys Renal calculus Kidney stone Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 19

20 Disorders of the Urinary System Renal failure Absence of urine formation Uremia Condition in which the kidneys do not filter the blood Urethritis Acute or chronic inflammation of the urethra Urinary incontinence Inability to control urination Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 20

21 Disorders of the Urinary System Urinary retention Inability to urinate when the urge is felt or the bladder is full Urinary tract infection Usually caused by bacteria and may affect the bladder, kidneys, or prostate Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 21

22 Issues and Innovations Dialysis Filtration of body fluids through a machine instead of the kidneys to remove excess water and waste Hemodialysis (HD) Filtration of the blood using an artificial membrane Venous blood is filtered slowly through the machine. Takes several hours to complete the process May be required two or three times per week to replace the failed kidney function Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 22

23 Lifestyle Changes of Dialysis Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 23

24 Issues and Innovations Dialysis Continuous abdominal peritoneal dialysis (CAPD) A cannula is inserted into the abdominal cavity. A solute of glucose and salts is instilled into the abdominal cavity to combine with the waste products. Fluid is drained out by means of gravity. Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 24

25 Issues and Innovations Five types of home dialysis Continuous ambulatory peritoneal dialysis Uses peritoneal to filter wastes and no machinery Surgically implanted tube filled with dialysate solution Solution manually put in and taken out of the abdomen Continuous cycling peritoneal dialysis Same as above but uses a filtering machine Conventional home hemodialysis Performed two or three times per week with hemodialysis machine Daily home hemodialysis Same as above but performed daily Nocturnal home hemodialysis Same as above but performed while patient is sleeping Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 25

26 Issues and Innovations Kidney transplantation Drawbacks include matching tissues, expense, and shortage of donors. High success rate Regenerative medicine process (Wake Forest Institute for Regenerative Medicine in North Carolina) Regrowth of organs Cells from the patient s body are cultivated in Petri dishes and layered into three-dimensional models of the organ. Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 26

27 Cost of Transplants Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 27

28 Lithotripsy Issues and Innovations Extracoporeal shock wave lithotripsy (ESWL) Uses high-energy pressure or sound waves to disintegrate kidney stones Shock waves sent through water or air Prevents need for surgery to remove stone Up to 2000 shocks may be necessary to dissolve stone Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 28

29 Lithotripsy FIGURE 17-6 A, Lithotripsy allows removal of kidney stones without surgery. (A, Courtesy Siemens Medical Systems, Inc.) Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 29

30 Summary Functions of the urinary system Regulating the composition of body fluids Removing wastes by filtering the blood Structures of the urinary system Kidneys Ureters Bladder Urethra Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 30

31 Summary Structures of the kidney Glomerulus Bowman s capsule Loop of Henle Collecting duct Components of normal urine Water Yellow color A ph of about 6 Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 31

32 Review Question The average ph of urine should be: a. 6 b. 7 c. 5 d. 8 e. 4 Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 32

33 Review Question The average ph of urine should be: a. 6 b. 7 c. 5 d. 8 e. 4 Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 33

34 Review Question The disorder of the urinary system known as renal failure is: a. A condition in which the kidneys do not filter blood b. The absence of urine formation c. Acute or chronic inflammation of the urethra d. The inability to urinate when the urge is felt or the bladder is full e. Usually caused by bacteria and may affect the bladder, kidneys, or prostate Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 34

35 Review Question The disorder of the urinary system known as renal failure is: a. A condition in which the kidneys do not filter blood b. The absence of urine formation c. Acute or chronic inflammation of the urethra d. The inability to urinate when the urge is felt or the bladder is full e. Usually caused by bacteria and may affect the bladder, kidneys, or prostate Copyright 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc. 35